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[PMID]: | 28882644 |
[Au] Autor: | Weon H; Kim TW; Youn DH |
[Ad] Endereço: | Department of Oral Physiology, BioCure Laboratory, School of Dentistry, Kyungpook National University, 2177 Dalgubeol Blvd, Jung-gu, Daegu 41940, Republic of Korea. |
[Ti] Título: | Postsynaptic N-type or P/Q-type calcium channels mediate long-term potentiation by group I metabotropic glutamate receptors in the trigeminal oralis. |
[So] Source: | Life Sci;188:110-117, 2017 Nov 01. | [Is] ISSN: | 1879-0631 |
[Cp] País de publicação: | Netherlands |
[La] Idioma: | eng |
[Ab] Resumo: | AIMS: Both N-type and P/Q-type voltage-gated Ca channels (VGCCs) are involved in the induction of long-term potentiation (LTP), the long-lasting increase of synaptic strength, in the central nervous system. To provide further information on the roles of N-type and P/Q-type VGCCs in the induction of LTP at excitatory synapses of trigeminal primary afferents in the spinal trigeminal subnucleus oralis (Vo), we investigated whether they contribute to the induction of LTP by activation of group I metabotropic glutamate receptors (mGluRs). MAIN METHODS: (S)-3,5-Dihydroxyphenylglycine (DHPG; 10µM for 5min), the group I mGluR agonist, was used to induce LTP of excitatory postsynaptic currents that were evoked in the Vo neurons by stimulating the trigeminal track. KEY FINDINGS: Weak blockade of the N-type or P/Q-type VGCCs by ω-conotoxin GVIA or ω-agatoxin IVA, respectively, which inhibited only 20-40% of Ca currents recorded in isolated trigeminal ganglion neurons but had no effect on the basal excitatory synaptic transmission, completely blocked the induction of LTP. In contrast, stronger blockade of the channels, which inhibited >50% of Ca currents and about 30% of basal synaptic transmission, resulted in the development of long-term depression (LTD), the long-lasting decrease of synaptic strength. Interestingly, the postsynaptic mechanism of DHPG-induced LTP, which was determined by paired-pulse ratio, disappeared when LTP was blocked, or LTD occurred, while a presynaptic mechanism still remained. SIGNIFICANCE: Our data suggest that postsynaptic N-type and P/Q-type VGCCs mediate the DHPG-induced LTP at the trigeminal afferent synapses in the Vo. |
[Mh] Termos MeSH primário: |
Canais de Cálcio Tipo N/fisiologia Canais de Cálcio Tipo P/fisiologia Canais de Cálcio Tipo Q/fisiologia Potenciação de Longa Duração/fisiologia Receptores de Glutamato Metabotrópico/fisiologia Núcleo Espinal do Trigêmeo/fisiologia
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[Mh] Termos MeSH secundário: |
Agatoxinas/farmacologia Animais Agonistas dos Canais de Cálcio/farmacologia Bloqueadores dos Canais de Cálcio Cromonas/farmacologia Feminino Potenciação de Longa Duração/efeitos dos fármacos Depressão Sináptica de Longo Prazo/efeitos dos fármacos Depressão Sináptica de Longo Prazo/fisiologia Masculino Terminações Pré-Sinápticas/fisiologia Ratos Receptores de Glutamato Metabotrópico/agonistas Potenciais Sinápticos/fisiologia Transmissão Sináptica/efeitos dos fármacos Núcleo Espinal do Trigêmeo/efeitos dos fármacos ômega-Conotoxinas/farmacologia
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[Pt] Tipo de publicação: | JOURNAL ARTICLE |
[Nm] Nome de substância:
| 0 ((S)-3,7-dihydroxychroman-4-one); 0 (Agatoxins); 0 (Calcium Channel Agonists); 0 (Calcium Channel Blockers); 0 (Calcium Channels, N-Type); 0 (Calcium Channels, P-Type); 0 (Calcium Channels, Q-Type); 0 (Chromones); 0 (Receptors, Metabotropic Glutamate); 0 (omega-Conotoxins) |
[Em] Mês de entrada: | 1709 |
[Cu] Atualização por classe: | 170929 |
[Lr] Data última revisão:
| 170929 |
[Sb] Subgrupo de revista: | IM |
[Da] Data de entrada para processamento: | 170909 |
[St] Status: | MEDLINE |
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